Population structure of hyperinvasive serotype 12F, clonal complex 218 Streptococcus pneumoniae revealed by multilocus boxB sequence typing.
Population structure of hyperinvasive serotype 12F, clonal complex 218 Streptococcus pneumoniae revealed by multilocus boxB sequence typing.
复制标题
通过多位点 boxB 序列分型揭示的高侵袭性血清型 12F、克隆复合物 218 肺炎链球菌的群体结构。
DOI：
10.1016/j.meegid.2011.08.016
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Robinson,DAshley
中科院分区：
文献类型：
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作者：
Rakov,AlexeyV;Ubukata,Kimiko;Robinson,DAshley
在过去的二十年里，美国至少发生了四次由血清型12F，克隆复合体218肺炎链球菌引起的侵袭性疾病的爆发。我们使用从美国34个州和其他8个国家收集的22年的203个暴发和监测分离株样本研究了这种克隆复合体的种群结构。传统的多位点序列分型确定了五种类型，并将一次爆发与其他爆发区分开来。为了提高分型分辨率，多位点boxB序列分型（MLBT）从10个可变boxB小卫星位点。MLBT确定了86种类型，并区分了四次爆发中的每一次。boxB基因座的多样性往往与重复序列大小呈正相关，总体而言，最适合无限等位基因突变模型。多位点连锁不平衡是强大的，但成对的不平衡减少与位点之间的物理距离，是最强的一个大区域的染色体，表明最近的重组。在样本中确定了两个主要的集群，它们在地理上是不同的，如美国西部和更东部的集群，在时间上是肺炎球菌结合疫苗许可之前和之后占主导地位的集群。这两个集群内的多样性和连锁不平衡也不同，表明不同的人口动态。MLBT揭示了这些高度侵袭性肺炎球菌的群体结构的隐藏方面，它可能为其他肺炎球菌克隆复合体的爆发调查，监测和群体遗传学研究提供有用的辅助工具。
At least four outbreaks of invasive disease caused by serotype 12F, clonal complex 218 Streptococcus pneumoniae have occurred in the United States over the past two decades. We studied the population structure of this clonal complex using a sample of 203 outbreak and surveillance isolates that were collected over 22years from 34 US states and eight other countries. Conventional multilocus sequence typing identified five types and distinguished a single outbreak from the others. To improve typing resolution, multilocus boxB sequence typing (MLBT) was developed from 10 variable boxB minisatellite loci. MLBT identified 86 types and distinguished between each of the four outbreaks. Diversity across boxB loci tended to be positively correlated with repeat array size and, overall, best fit the infinite alleles mutation model. Multilocus linkage disequilibrium was strong, but pairwise disequilibrium decreased with the physical distance between loci and was strongest in one large region of the chromosome, indicating recent recombinations. Two major clusters were identified in the sample, and they were differentiated geographically, as western and more easterly US clusters, and temporally, as clusters that predominated before and after the licensure of pneumococcal conjugate vaccines. The diversity and linkage disequilibrium within these two clusters also differed, suggesting different population dynamics. MLBT revealed hidden aspects of the population structure of these hyperinvasive pneumococci, and it may provide a useful adjunct tool for outbreak investigations, surveillance, and population genetics studies of other pneumococcal clonal complexes.